Update .gitignore files to ignore typical dev side products

Add / update .gitignore files for tests/ and tools to ignore
binaries, logs, traces typically produced during development.

 * tests/.gitignore: exclude tests binaries and test results
 * tools/.gitignore: update to ignore produced binaries

Signed-off-by: Matthias Maennich <maennich@google.com>

tests/.gitignore

@@ -0,0 +1,30 @@
+*.log
+*.py
+*.sh
+*.svg
+*.trs
+*.txt
+
+output/
+
+mockfedabipkgdiff
+printdifftree
+runtestabicompat
+runtestabidiff
+runtestabidiffexit
+runtestaltdwarf
+runtestannotate
+runtestcorediff
+runtestdiffdwarf
+runtestdiffdwarfabixml
+runtestdifffilter
+runtestdiffpkg
+runtestdiffsuppr
+runtestini
+runtestlookupsyms
+runtestreaddwarf
+runtestreadwrite
+runtestsvg
+runtesttypesstability
+testdiff2
+testirwalker

tools/.gitignore

@@ -1,5 +1,8 @@
-/biar
-/bidiff
-/bidw
-/bilint
-/bisym
+abicompat
+abidiff
+abidw
+abilint
+abinilint
+abipkgdiff
+abisym
+kmidiff